Commercially available sorters consist of a transport system, usually of a chain conveyor construction, which carries trays on the top of an endless chain. These trays are loaded with items to be sorted, carried to a selected outlet (i.e., receiving) position (i.e., station) and tipped, whereby the item carried is dropped into a receptacle. The trays are reset before re-entering the loading area. However, existing transport systems are limited to a single level of trays.
One conventional tilt tray sorter generally comprises a moving chain which can carry a tilting element which includes a tray and a tilting mechanism. Such a parcel handling device, for example the 3D Tilt Tray Sorter is available from Beumer Pty Limited, 293A Seaview Road, Henley Beach, South Australia, 5022.